title: BAFF- and APRIL-dependent maintenance of antibody titers after immunization with T-dependent antigen and CD1d-binding ligand.
abstract: CD1d-restricted invariant NKT (iNKT) cells boost humoral immunity to T-dependent Ags that are coadministered with the CD1d-binding glycolipid Ag α-galactosylceramide (α-GC). Observations that mice lacking iNKT cells have decaying Ab responses following vaccination have led to the hypothesis that iNKT cells express plasma cell (PC) survival factors that sustain specific Ab titers. Bone marrow chimeric mice in which the entire hematopoietic compartment or iNKT cells selectively lacked BAFF, a proliferation-inducing ligand (APRIL), or both BAFF and APRIL were created and immunized with nitrophenol hapten-conjugated keyhole limpet hemocyanin adsorbed to Imject aluminum hydroxide-containing adjuvant or mixed with α-GC. In comparison with BAFF- or APRIL-sufficient bone marrow chimeras, absence of hematopoietic compartment- and iNKT-derived BAFF and APRIL was associated with rapidly decaying Ab titers and reduced PC numbers. The iNKT cell-derived BAFF or APRIL assumed a greater role in PC survival when α-GC was used as the adjuvant for immunization. These results show that iNKT cell-derived BAFF and APRIL each contribute to survival of PCs induced by immunization. This study sheds new light on the mechanisms through which iNKT cells impact humoral immunity and may inform design of vaccines that incorporate glycolipid adjuvants.
authors.affiliation: Department of Microbiology and Immunology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA.
authors.forename: Hemangi B
authors.initials: HB
authors.lastname: Shah
authors.forename: Sunil K
authors.initials: SK
authors.lastname: Joshi
authors.forename: Pragya
authors.initials: P
authors.lastname: Rampuria
authors.forename: T Scott
authors.initials: TS
authors.lastname: Devera
authors.forename: Gillian A
authors.initials: GA
authors.lastname: Lang
authors.forename: William
authors.initials: W
authors.lastname: Stohl
authors.forename: Mark L
authors.initials: ML
authors.lastname: Lang
mesh_terms: D000276:Adjuvants, Immunologic / Q000008:administration & dosage*; D000536:Aluminum Hydroxide / Q000008:administration & dosage / Q000276:immunology; D000818:Animals; D000906:Antibodies / Q000097:blood*; D055610:Antigens, CD1d / Q000276:immunology; D053264:B-Cell Activating Factor / Q000172:deficiency / Q000235:genetics / Q000378:metabolism*; D001854:Bone Marrow Cells; D005260:Female; D005699:Galactosylceramides / Q000008:administration & dosage / Q000276:immunology; D006433:Hemocyanins / Q000008:administration & dosage / Q000276:immunology; D056724:Immunity, Humoral; D007114:Immunization; D051379:Mice; D018345:Mice, Knockout; D055611:Natural Killer T-Cells / Q000276:immunology*; D010950:Plasma Cells / Q000378:metabolism; D018183:Transplantation Chimera; D053300:Tumor Necrosis Factor Ligand Superfamily Member 13 / Q000172:deficiency / Q000235:genetics / Q000378:metabolism*; D014611:Vaccination
chemical_list: D000276:Adjuvants, Immunologic; D000906:Antibodies; D055610:Antigens, CD1d; D053264:B-Cell Activating Factor; D005699:Galactosylceramides; C491959:Tnfsf13 protein, mouse; C505720:Tnfsf13b protein, mouse; D053300:Tumor Necrosis Factor Ligand Superfamily Member 13; C493154:alpha-galactosylceramide; D000536:Aluminum Hydroxide; D006433:Hemocyanins; C032808:keyhole-limpet hemocyanin